Collapsible tap.



No. 784,208. PATENTBD MAR. '7, 1905. P. A. ERRINGTON.

GOLLAPSIBLE TAP.

APPLICATION FILED AUG. 21, 1900.

itwaooco: I 4 I I anucnfoz Patented March "Y, 1905.

YET triple.

GOLLAFSIIBLE TAFK SPECIFICATION forming part of Letters Patent No. 784,208, dated March *7, 1905.

7 Application filed August 21, 1900. Serial No. 27,553.

To rill 1077/0111, 732$ III/(Ly concern:

Be it known that I, FRANKLIN ALFRED Ea- RINGTON, a citizen of the United States of America, residing in New York city, borough of Richmond, State of New York, (post-office Stapleton, New Yorl have invented certain new and usefulimprovements in Collapsible Taps, of which the following is a specification.

My invention relates more particularly to taps in which the chasers or jaws move longitudinally of the supporting-body to open to and close from the cutting position; and the principal object of my invention is to provide a simple means of adjusting the cutting diameter of the jaws and of retaining the chasers in cooperative position relatively to the body; and my invention further consists in the novel details of improvement that will be more fully hereinafter set forth and then pointed out in the claims.

Reference is to be had to the accompanying drawings, forming a part hereof, wherein- Figure 1 represents a plan view of the cutting end of adevice embodying my invention, the jaws being shown in the cutting position. Fig. 2 is a vertical cross-section on the line 2 2 of Fig. 1, the jaws being shown in the collapsed position; and Fig. 3 is a similar view except that the chasers are shown in the cutting position. Fig. at is a cross-section of Fig. 3 on the line 4 4, showing a method of camming the external thrust-faces of the device to render them adjustable; and Fig. 5 is a plan view of the rear or driving end of the device, showing a method of holding the center piece from movement independently of the body.

Similar numerals and letters of reference indicate corres 'ionding parts in the several held in any one of a series of desired, positions relatively to body 1 by the set-screws l engaging an adjusting-nut (i, the latter meshing with a SOlB\V-tlll()2t(Il0(l projection 3 of center piece 3 and hold in any desired position therealong by any usual nutlock arrangement, such as the jam-nut H. The nut (i is flattened on the sides to bear squarely upon the Hat ends of the set-screws 1.". This arrangement holds the center piece 3 from inde pendent movement in any direction relatively to body 1. The center piece 3 is provided with a longitudinal succession of {)I'UjOClllOllS l and indentures F. The outer surfaces 3 of the projectioi'is 1+) are shown cammed. laterally of the center piece 3 to provide adjustable external thrustdacesifi" thereupon. (See Fig. i.) The chaser or chasers 2 are inserted in slot or slots 1, the inner end of each chaser abutting against its respective slot-stop face 1 when in the cutting position, each chaser being thus connected to rotate in unison with body 1 and left radiallyand longitiulinally movable rela tively to body 1. The outer end surface of each chaser is provided with sorratitms 2, extending transversely of the chaser at an oblique angle to the axis of the body 1. or screw-cutting teeth of any desired pitch. 1. have shown the inner end portion 0 f the chaser having a transverse groove 0 to receive a retaining and alining spring 4-, whose ends are joined together in such a manner as to enable said spring to surround the chasers 2 and body 1 and exert a yieldil'ig pressure against the movementof chaser-s 2 outwardly radially of the body .1. To protect spring 4:, I preferably surround it by guards a" at each intersection with the chasers 2. The portion of the jaws provided with the spring-groove 0 is prefer ably shown projecting beyond the periphery of the body si'dliciently to enable the spring to clear the periphery of body 1 when the chasers 2 are in the collapsed position, and the grooveo preferably deep enough to hold the spring 4: in mesh with the jaws or chasers 2 durin the movement of the s )rin L lon itudinally of the body with the chasers 2.

The eollapslng and expanding of the Chasers 2 1s effected by prov idlng the inner surface of each chaser with a longitudinal succession of projections and indentures f, corresponding with the projections E and indentures F of the center piece 3. The inner ends 2 of the projections 6 provide internal thrust-faces for the chaser that bear upon the external thrustfaces 3 of the center piece 3 during operation, and the indentures F of the center piece 3 receive the projections e at the same time that the indentures f receive the projections E of the center piece 3 when the jaws are in the collapsed position. The outer sides 4: of the chaser projections (i and the inner sides V of the body projections E are preferably left straight to provide coacting stop-faces to arrest the outward.longitudinal movement of the jaws 2, whereas the opposite sides of the projections e E are preferably sloped at s to move the jaws radially of the body 1 when the jaws move longitudinally inwardly of body 1 from the collapsed to the cutting position.

WVhenever it is desirable to adjust the cutting diameter of the chasers 2, the set-screws 1 can be slacked back and the center piece 3 either partially or entirely removed from body 1 through bore In. The lock-nut H is then slacked back, that the adjusting-nut Gr may be turned upon the screw-tln'eaded portion 3 proportionately to the desired relative angular' adjustment of the cam-faces E with the radial slots 1. Thereupon the lock-nut H is tightened up against the adjusting-nut G, which again locks the latter in its new position upon center piece 3. Vhen the center piece 3 is now placed in operative position in bore (1:, the tightening up of the set-screws 1 upon the flats of adjusting-nut G will cause a par tial rotation of center piece 3 relatively to its former position in body 1, thereby securing an angular adjustment of the cam-faces E relatively to the slots 1, which will bring a new section of the cam-faces E under the chasers 2, so that these new external thrust-faces 3 (being that portion of the cam-faces E upon which the internal thrust faces 2 of the chasers 2 bear when in the cutting position) will now be located at a different position along the outermost surfaces of the cams E, and consequently at a greater or lesser distance from the center of body 1, which will make a corresponding variation in the projection of the chasers 2 from the periphery of body 1 when said chasers are in the cutting position. The ability to adjust the cutting diameter of the chasers is a very essential feature, as some adjustment should always be provided to enable the chasers to cut a tight or loose fit, compensate for any variation in hardening, &c.

An abutment or pin 5 prevents the chasers 2 from slipping out of the cutting position under the action of gravity when the device is used vertically, as said pin engages the guard 1 of spring 4 for said purpose. The coacting surfaces of abutment 5 and springguard 1* are adapted to coact together in such a manner as to form ayielding catch by rounding one of said coacting surfaces sufliciently to permit the springguards r to rise over the abutment or abutments 5 when the chasers 2, spring 4, and spring-guards 1 are moved 7 longitudinally of body 1 by sufficient force to expand the spring 1. The spring-guards r are shown adapted to mesh with the chasers 2 to equalize the movement of the chasers 2, and for this purpose I have preferably shown indentures 0, provided in the chasers 2 to receive the spring-guards 1.

The parts being in the collapsed position shown in Fig. 2, the operation is as follows: The chasers 2 are pushed inwardly of body 1 30 along their respective slots 1 by pressure suitably applied against their extended outer ends, the spring 4L preserving the alinement of the chasers with the body at all times by pressing the chaser projections 6 against the center 5 piece 3, the sloping faces 5- S causing the chasers to move radially outwardly of body 1.

hen the inner ends of the chasers abut against the stop-faces 1 of the slots,thechasers will be in their respective operative or cut- 9 ting positions. This opening of the chasers 2 can be accomplished during the rotation of the device by pressing the outer ends of the chasers against a suitable surface having an aperture that will admit the outer end 1" of the body. Upon the rotation of either my device or a suitable piece of work having a suitable aperture to be internally threaded or tapped the teeth 2 of chasers 2 will cut screwthreads into the walls of said aperture upon I00 presentation of the device thereagainst, and

the position of the chasers 2 relatively to body 1 willremain constant until the relative movement of the device and the work toward each other is stopped by any suitable means 5 as, for instance, by using the outer end 1 of the body as a stop to encounter the bottom surface of the aperture being tln'eaded,whereupon the continued rotation of the rotative member (either body 1 or the work being operated upon) will cause the chasers 2.to continue cutting, while at the same time the oblique serrations 2 of the chasers 2 will draw the chasers 2 longitudinally of body 1 during the cutting operation independently 5 of the external thrustfac'es 3 by the spiral coaction of the oblique serrations 2 with the' threads already cut in the work until the internal thrustfaces 2 of the chasers 2 pass out of line with the external thrust-faces 3 of the I20 body 1, whereupon the jaws or chasers 2 will slide inwardly radially of body 1, the projections 6 of the chasers passing within the plane of their respective associate external thrustfaces 3 into the indentures F of the body 1, 5 and the projections E of the body simultaneously entering the indenturesf of the chasers,

and this inward radial movement of the chasers continues during the collapsing operation until the cutting edges of the teeth 2 3 mazes clear the threaded walls of the aperture in the work, whereupon the device can be withdrawn from the threaded aperture without stopping or reversing the rotation of the rotativemember, (either body 1 or the work beingoperated upon.

Having now described my invention, what l claim is- 1. The combination of a body provided with a longitudinal succession of projections and indentures the outer ends of the body projections providing external thrust-faces, a chaser or chasers connected with the body to rotate in unison therewith and movable laterally and longitudinally thereof, the outer surface of each chaser being provided with serrations extending at an oblique angle to the axis of the body and the inner surface of each chaser having a longitudinal succession of projections and indentures the inner ends of the chaser projections providing internal thrustfaces that bear upon said external thrust-faces during the cutting operation and that pass within the plane of their respective associate external thrust-faces during the collapsing operation, each chaser being adapted to be drawn longitudinally of the body independently of said external thrust-faces through the medium of its oblique serrations during the cutting operation to bring the internal thrust-faces out of line with their respective associate ex ternal thrust-faces to permit the chaser to slide inwardly laterally of the body, substantially as described. 7

2. The combination of abody provided with l a longitudinal succession of projections and indentures the outer ends of the body projections providing external thrust-faces, a chaser or chasers connected with the body to rotate in unison therewith and movable laterally and longitudinally thereof, the outer surface of each chaser being provided with serrations extending at an oblique angle to the axis of the body and the inner surface of each chaser having a longitudinal succession of projections and indentures the inner ends of the chaser projections providing internal thrustment of each chaser longitudinally of the body, substantially as described.

3. The combination of a body provided with a longitudinal succession of projections and indentures the outer ends of the body projections providing external thrust-faces, a chaser or chasers connected with the body to rotate in unison therewith and movable laterally and longitudinally thereof, the outer surface of each chaser being provided with scrra' tions extendii'ig at an oblique angle to the axis of the body and the inner surface of each chaser having a longitudinal succession of projections and lllClGlllilll'lBS the inner ends of the chaser projections providing internal thrust-faces that bear upon the external thrustfaccs during the cutting operation and that pass within the plane of their respective associate external thrust-faces during the collapsing operation, each chaser bcing adapted to be drawn longitudinally of the body independently of said external thrustfaces through the medium of its oblique serrations during the cutting operation, and a spring adapted to press the chaser or chasers toward and retain said chaser or chasers in alinement with the axis of the body, substantially as described.

4C. The combination of a body provided with a longitudinal succession of projections and indentures the outer ends of the body projections providing external thr ustfaces, a chaser or chasers connected with the body to rotate in unison therewith and movable laterally and longitudinally thereof, the outer surface of each chaser being provided with serrations extending at an oblique angle to the axis of the body and the inner surface of each chase-r hav ing a longitudinal succession of projections and indentures the inner ends of the chaser projections providing internal thrust-faces that bear upon the external thrust-faces during the cutting operation and that pass within the plane of their respective associate external thrust-faces during the collapsing opera tion, each chaser being adapted to be drawn longitudinally of the body iinlepeitidently of said external thrust-faces through the medium of its oblique serrations during the cutting operation, and a spiral spring having its ends connected together, said spring surrounding the body and chaser or chasers and exerting a yielding pressure against the movement of the chaser or chasers outuntrdly radially of the body, substantially as described.

The combination of a body provided with a longitudinal succession of projections and indentures the outer ends of the body projections providing external thrust-faces, a chaser or chasers connected with the body to rotate in unison therewith and movable laterally and longitudinally thereof, the outer surface of each chaser being provided with serrationsextending at an oblique angle to the axis of the body and the inner surface of each chaser having a longitudinal succession of projections and indentures the inner ends of the chaser projections providing internal thrust-faces that bear upon the external thrust-faces during the cutting operation and that pass within Its the plane of their respective associate external thrust-faces during the collapsing operation, and a spring surrounding the body and the chaser or chasers and exerting a yielding pressure against the movement of the chaser or chasers outwardly radially of the body, each chaser being adapted to be drawn longitudinally of the body independently of said external thrust-faces through the medium of its oblique serrations during the cutting operation, and the spring being connected with the chaser or chasers to move in unison therewith longitudinally of the body, substantially as described.

6. The combination of a body provided with radial slots, chasers located in the slots and movable radially and longitudinally of the body, an abutment rigidly carried by the body and a spring surrounding the body and chasers, one of the edges of said last-named elements being rounded to enable said spring to coact with the abutment to form a yielding catch to regulate the movement of the chasers longitudinally of the body, substantially as described.

7. The combination of a body provided with radial slots, chasers located in the slots and movable radially and longitudinally of the body, an abutment rigidly carried by the body, a spring surrounding the body and chasers, one of the edges of said last-named elements being rounded to enable said spring to coact with the abutment to form a yielding catch to regulate the movement of the chasers longitudinally of the body, and a spring-guard interposed between the spring and the chasers at their intersections and meshing with the chasers to equalize their movements, substantially as described.

8. The combination of a body provided with a longitudinal succession of projections and indentures the outer ends of the body projections providing external thrust-faces, a chaser or chasers connected with the body to rotate in unison therewith and movable laterally and longitudinally thereof, the outer surface of each chaser being provided with serrations extending at an oblique angle to the axis of the body and the inner surface of each chaser having a longitudinal succession of projections and indentures the inner ends of the chaser projections providing internal thrust-faces that bear upon the external thrust-faces during the cutting operation and that pass within the plane of their respective associate external thrust-faces during the collapsing operation, means to adjust the external thrust-faces laterally of the body, and means to retain the ex ternal thrust-faces in position when adjusted, each chaser being adapted to be drawn longitudinally of the body independently of the external thrust-faces through the medium of its oblique serrations during the cutting operation, substantially as described.

9. The combination of a body havinga longitudinal succession of projections and indentures the outermost surfaces of the projections providing external thrust-faces which are located upon cam-faces which slope transversely of the axis of the bodyinwardly from their outermost points to render said external thrustfaces adjustable, a chaser or chasers connected with the body to rotate in unison therewith and movable radially thereof, the inner surface of each chaser being provided with a correspondthe inner ends of the chaser projections providing internal thrust-faces that bear upon the external thrust-faces during the cutting operation and that pass within the plane of their respective associate external thrust-faces during the collapsing operation, one of said parts provided with said succession of projections and indentures being movable longitudinally of the other of'said parts so provided, means to adjust the location of said external thrustfaces along said cam-faces relatively to said chasers, and means to hold said cam-faces from rotation independently of body 1 during the collapsing operation, substantially as described.

1.0. The combination of a body having a longitudinal succession of projections and indentures the outermost surfaces of the projections providing external thrust-faces which are located upon cam-faces which slope transversely of the axis of the body inwardly from their outermost points to render said external thrust-faces adjustable, a chaser or chasers connected with the body to rotate in unison therewith and movable laterally and longitudinally thereof, the outer surface of each chaser being provided with serrations extending at an oblique angle to the axis of the body and the inner surface of eaclrchaser having a longitudinal succession of projections and indentures the inner ends of the chaser projections providing internal thrust-faces that bear upon said external thrust-faces during the cutting operation and that pass within the plane of their respective associate external thrust-faces during the collapsing operation, each chaser being adapted to be drawn longitudinally of the body independently of said external thrust-faces through the medium of its oblique serrations during the cutting operation, means to adjust the location of said external thrust-faces along said cam-faces relatively to said chasers, and means to hold said cam-faces from rotation independently of body 1 during the collapsing operation, substantially as described. I

11. The combination of a body having an axial bore, a center piece located in the axial bore and provided with a longitudinal succession of projections and indentures the outer ends of the projections providing external thrust-faces, a chaser or chasers connected with the body to rotate in unison therewith and movable laterally and longitudinally thereof,

ing succession of projections and indentures the outer surface of each chaser being provided with serrations extending at an oblique angle to the axis of the body and the inner surface of each chaser having a longitudinal succession of projections and indentures the inner ends of the chaser projections providing internal thrust-faces that bear upon said external thrust-faces during the cutting operation and that pass within the plane of their respective associate external thrust-faces dur ing the collapsing operation, each chaser being adapted to be drawn longitudinally of the body independently of the external thrustfaces through the medium of its oblique serrations during the cutting operation, substantially as described.

12. The combination of a body having an axial bore, a center piece located in the axial bore and provided with a longitudinal succession of projections and indentures the outermost surfaces of the projections providing external thrust-faces which are located upon cam-faces which slope transversely of the axis of the body inwardly from their outermost points to render said external thrust-faces adjustable, and a chaser or chasers connected with the body to rotate in unison therewith and movable radially thereof, the outer surface of each chaser being provided with serrations extending at an oblique angle to the axis of the body and the inner surface of each chaser having a longitudinal succession of n'ojections and indentures the inner ends of the chaser projections providing internal thrust-faces that bear upon said external thrust-faces during the cutting operation and that pass within the plane of their respective associate external thrust-faces during the collapsing operation, one of said parts provided with said succession ofprojections and indentures being movable longitudinally of the other of said parts similarly provided, means to adjust the location of said external thrustfaces along said cam-faces relatively to said chasers, and means to hold said cam faces "from rotation independently of body tl' the collapsing operation, substantially as described.

13. The combination of a body having an axial bore, a center piece located in the axial bore and provided with a longitudinz'il succession of projections and indentures the outermost surfaces of the projections providing external thrust-faces which are cainmed transversely of the axis of the body inwardly from their outermost points to render said external thrustfaces ad j ustable,and a chaser or chasers connected with the body to rotate in unison therewith and movable radially thereof, the outer surface of each chaser being provided with serrations extending at an oblique angle to the axis of the body and the inner surface of each chaser having a longitudinal succession of projections and indentures the inner ends of the chaser projections providing internal thrust-faces that bear upon the external thrust-faces during the cutting operation and that pass within the plane of their respective associate external thrust-faces during the collapsing operation, one of said parts provided with said succession of projections and indentures being movable longitudinally of the other of said parts similarly 'n'ovided, and means to hold the center piece from rotation independently of the body in any one of a series of adjusted positions, substantially as described.

l t. The combination of a body having an axial bore, a center piece located in the axial bore and provided with a longitudinal succession of projections and indentures the outermost surfaces of the projections providi ng external thrustdaces which are cainmed trans- Versely of the axis of the body inwardly from their outermost points to render said external thrust-faces adjustable, and a chaser or chasers connected with the body to rotate in unison therewith and movable radially thereof, the outer surface of each chaser being provided with serrations extending at an oblique angle to the axis of the body and the inner surface of each chaser having a longitudinal succ sion of projections and indentures the inner ends of the chaser projections providing internal thrust-faces that bear upon the external thrust faces during the cutting operation and that pass within the plane of their respective associate external thrust-faces during the col lapsing operation, one of said parts provided with said succession of projectionsand indentures being movable longitudinally of the other of said parts similarly provided, the center piece having a screw-threzdled projection, and a nut meshing with said screwthreaded projection and adapted to hold the center piece from rotation independently of the body in any one of a series of adjusted positions relatively thereto, substantially as described.

'15. The combimition of a body having an axial bore, a center piece located in the axial bore and provided with a longitudinal succession of projections and ii'nlentures the outermostsur faces of the projections providing ex ternal thrust-faces which are located upon cam-faces which slope transversely of ti 1 axis of the body inwardly from their outermost points to render said external thrust-faces ad justable, and a chaser or chasers connected with the body to rotate in unison therewith and movable radially thereof, the outer surface of each chaser being provided with serrations extending at an oblique angle to the axis of the body and the inner surface ofeach chaser having a longiti'ulinal succession of projections and indentures the inner ends of the chaser projections providing internal thrustdaces that bear upon the external th rustfaces during the cutting operation and that pass within the plane of their respectim assooiate external thrust-faces during the collapsto hold the center piece from rotation indeing operation, one of said parts provided With pendently of the body, substantially as de IO said succession of projections and indentui'es scribed.

be ng movable longitudinally of the othel 0t FRANKLIN ALFRED ERRINGTON. said parts similarly provided, means to ad ust the location of said external thrust-faces along lVitnesses:

A. H. FISHER, D. J. WILsoN.

said cam-faces relatively to said chaser-s, and a set-screw carried by the body and adapted 

